Hopefully someone here knows about ZX's too.

My father inlaw gave my daughter his 82 ZX and it hadn't been started in awhile. Turn's out it's been "quite" a while and the gas was awful. We put some new gas in with the old and started it by pouring a little gas into the intake. It ran so bad that we drained the tank, purged the fuel system replaced the plugs, cap, rotor, and fuel filter and tried again.

Even with new gas in the tank and fuel rail it won't start on it's own, and if you get it to run it runs rough. I'm guessing that I should check the cold start valve, but even if that has a problem I can fix it doesn't explain why it runs so bad when it's primed and started.

Is there something that could have happened as a result of running the bad gas through it ? Maybe it messed up the O2 sensor, or the Cat ?

Thanks for any help guys!

You have been here for a while, so I won't use the SEARCH card...That being said, the ZX motor is the same L28 motor on the Zs. It just has more stuff bogging it down.

Have you replaced the plugs or checked the ignition wires and distributor for corrosion/rodentia/tight fittings? Is there a ratnest in the intake? Are ALL the ground connectios free from corrosion? Is the oil in decent shape? What was the reason for the car not being used in the first place?

If you haven't guessed by now, there are MANY reasons why an old car that has been sitting for a while won't start right off the bat.

If you haven't guessed by now, there are MANY reasons why an old car that has been sitting for a while won't start right off the bat.

Yup, just start, one system at a time. Look at the plugs... look at the ignition coil, dizzy cap etc. etc.

Examining your fuel pressure might be a good place to begin too. Having sat for so long, there's bound to be varnish and other crud in the lines.

There's also a filter at the fuel pump that might be chock fuel of junk... and on the ZX's I think you can pull this from inside the car. This has been covered in a few threads, so the Search feature will behoove you.

Anyway... fuel supply is a good place to look.

Thanks for the responses,

I've checked the obvious stuff like rodents in the intake, plugs, cap, fuel filter, etc. It "ran when parked" and wasn't driven because a new car was purchased. It's been parked in a heated garage so I doubt it's corrosion on the connections, but I haven't ruled it out.

I'm wasn't aware of the fuel filter near the tank so I'll look into that. I drove it around the block a fews days ago and it wouldn't go over 40mph. It didn't cough, sputter, or stall, it just wouldn't go any faster. That sounds like a plugged Cat, but that's not easy to test. I'll try a few more things and let everyone know if I get it sorted out.

There is a filter on the sending unit, I would expect it to be clogged up, the ZX tank rusts just like your tank does after all.

Don't forget about the little filter inside the fuel pump (same as the 280z)-atlanticz.ca has a great tutorial on its removal.

Here is a photo of my old sending unit-you will see what appears to be a tea filter bag on the end-that was something the PO did (who knows why). If yours is original, you will find a cylindrical wire mesh/plastic unit there, which you should be able to clean up.

You say that it wouldn't go over 40mph-how high would it rev?

There is a filter on the sending unit, I would expect it to be clogged up, the ZX tank rusts just like your tank does after all.

Don't forget about the little filter inside the fuel pump (same as the 280z)-atlanticz.ca has a great tutorial on its removal.

Here is a photo of my old sending unit-you will see what appears to be a tea filter bag on the end-that was something the PO did (who knows why). If yours is original, you will find a cylindrical wire mesh/plastic unit there, which you should be able to clean up.

You say that it wouldn't go over 40mph-how high would it rev?

I know that filter well, it was completely clogged and collasped on my E-Type. Is there a way to trick the fuel pump into running continuously when the key is turned on ? That way I could run the line to the filter under the hood into a bucket and see if I'm getting a good flow.

The car seems to only Rev to about 3500rpm at idle.

Here are some shots from my troubleshooting section of the FSM. I would imagine there is a way to fool the fuel pump into staying on, though I might think it easier to check the fuel pressure with an applicable guage instead of hacking into your wires; though that's just an opinion.

Thanks for the pict's, I'll take a look. I'll have to get back to the group when I have more time. Right now I'm in the middle of a bathroom remo and need to get it completed before I can continue on the Z.

Standby.....